Navigation system

ABSTRACT

A navigation system includes: a map information acquiring unit for acquiring map information; an HOV lane decision unit for deciding whether an HOV lane is included in a road represented by the map information acquired by the map information acquiring unit or not; a road number processing unit for performing, when the HOV lane decision unit decides that the HOV lane is included, processing of adding information representing the HOV lane to a road number of the road including the HOV lane; and a display processing unit or a voice information unit for causing the road number passing through the processing by the road number processing unit to be displayed on the guide map or output in voice.

This application is a Divisional of co-pending U.S. Application No.13/131,134, filed on May 25, 2011. U.S. Application No. 13/131,134 isthe national phase of International Application No. PCT/JP2009/005743,filed on Oct. 29, 2009, which claims the benefit of priority toApplication No. 2008-304932 filed in Japan on Nov. 28, 2008. The entirecontents and disclosure of the above-referenced applications are allhereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a navigation system for guiding a userto a destination, and particularly to a technique for guiding whiletaking an HOV lane (High Occupancy Vehicle Lane) into account.

BACKGROUND ART

Conventionally, as a road that regulates entrance of vehicles, a carpoollane has been known which is employed by a road system mainly seen inlarge cities in North America. The carpool lane, which is also called anHOV lane, is a lane that allows only vehicles with two or morepassengers to travel. As an example of the carpool lane, a lane providedon a highway, a lane that short-cuts an interchange and the like areknown. A road system that employs the carpool lane encourages aplurality of passengers to get on the same vehicle by givingpreferential treatment to them of being able to arrive at a destinationin a shorter time by driving along the carpool lane, thereby trying toreduce a volume of traffic to alleviate traffic congestion.

As a technique for guiding along the carpool lane, Patent Document 1discloses a navigation system that enables driving along a laneefficiently which limits changing to or from other lanes. The navigationsystem reads from a DVD map data containing road information on anentrance/exit point on an express highway provided with a carpool lane,and stores in a data buffer. Using the map data stored in the databuffer, a route search processing unit performs route search processingconsidering whether the carpool lane can be used. To carry out routeguidance using the carpool lane, a carpool lane guiding unit givesprescribed lane change information using images and voices at timingwhen an entrance/exit point at which the route is to be changed comeswithin a prescribed distance from the position of the vehicle.

PRIOR ART DOCUMENT Patent Document

-   Patent Document 1: Japanese Patent Laid-Open No. 2001-183159.

DISCLOSURE OF THE INVENTION

However, the conventional technology disclosed in the foregoing PatentDocument 1 does not give information about the road number while takingan HOV lane into account, information about the remaining distance andremaining time as to the driving HOV lane, or information for displayingan entrance/exit section in a single link, thereby offering a problem inthat a user cannot drive along the HOV lane comfortably.

The present invention is implemented to solve the foregoing problems.Therefore it is an object of the present invention to provide anavigation system capable of guiding a user through an HOV lanecomfortably.

To solve the foregoing problems, a navigation system in accordance withthe present invention includes: a map information acquiring unit foracquiring map information; an HOV lane decision unit for decidingwhether an HOV lane is included in a road represented by the mapinformation acquired by the map information acquiring unit or not; and acontrol unit for checking, when the HOV lane decision unit decides thatthe HOV lane is included, whether a branch road diverging only from anordinary lane is located in a route section passing through the HOV laneor not on a basis of the map information acquired by the map informationacquiring unit, and for suppressing guidance of the branch road when adecision is made that the branch road is located.

According to the navigation system in accordance with the presentinvention, as for the branch road connected to the ordinary lane, sinceit is impossible to enter the branch road during traveling in the HOVlane, it can suppress giving information unnecessary for a usersince theinformation representing the HOV lane is added to the road number and isdisplayed during traveling in the HOV lane, it can cause a user tovisually recognize in which road and where on the road the user isdriving. As a result, it can give information that will enable the userto drive comfortably in the HOV lane.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a hardware configuration of anavigation system of an embodiment 1 in accordance with the presentinvention;

FIG. 2 is a functional block diagram showing a functional configurationof the controller of the navigation system of the embodiment 1 inaccordance with the present invention;

FIG. 3 is a flowchart showing the operation of the navigation system ofthe embodiment 1 in accordance with the present invention;

FIG. 4 is a diagram showing an example of an HOV lane information addedroad number displayed on the screen of a display of the navigationsystem of the embodiment 1 in accordance with the present invention;

FIG. 5 is a diagram showing another example of an HOV lane informationadded road number displayed on the screen of the display of thenavigation system of the embodiment 1 in accordance with the presentinvention;

FIG. 6 is a diagram showing still another example of an HOV laneinformation added road number displayed on the screen of the display ofthe navigation system of the embodiment 1 in accordance with the presentinvention;

FIG. 7 is a flowchart showing the operation of a navigation system of anembodiment 2 in accordance with the present invention;

FIG. 8 is a diagram showing processing of extracting the road numberfrom a road name, which is carried out by the navigation system of theembodiment 2 in accordance with the present invention;

FIG. 9 is a flowchart showing the operation of a navigation system of anembodiment 3 in accordance with the present invention;

FIG. 10 is a flowchart showing the operation of a navigation system ofan embodiment 4 in accordance with the present invention;

FIG. 11 is a diagram showing an example of displaying a remainingdistance or remaining time on the screen of a display of the navigationsystem of the embodiment 4 or 6 in accordance with the presentinvention;

FIG. 12 is a flowchart showing the operation of a navigation system ofan embodiment 5 in accordance with the present invention;

FIG. 13 is a flowchart showing the operation of a navigation system ofan embodiment 6 in accordance with the present invention;

FIG. 14 is a flowchart showing the operation of a navigation system ofan embodiment 7 in accordance with the present invention;

FIG. 15 is a flowchart showing the operation of a navigation system ofan embodiment 8 in accordance with the present invention;

FIG. 16 is a diagram showing an example of displaying a guide sectionmark in the navigation system of the embodiment 8 in accordance with thepresent invention;

FIG. 17 is a flowchart showing the operation of a navigation system ofan embodiment 9 in accordance with the present invention;

FIG. 18 is a flowchart showing the operation of a navigation system ofan embodiment 10 in accordance with the present invention;

FIG. 19 is a flowchart showing the operation of a navigation system ofan embodiment 11 in accordance with the present invention;

FIG. 20 is a diagram showing an example of displaying an HOV lane on aguide map in the navigation system of the embodiment 11 in accordancewith the present invention;

FIG. 21 is a flowchart showing the operation of a navigation system ofan embodiment 12 in accordance with the present invention;

FIG. 22 is a diagram showing an example of displaying a no entry mark ona map in the navigation system of the embodiment 12 in accordance withthe present invention;

FIG. 23 is a diagram showing an example of displaying a no entry mark ona guide map in the navigation system of the embodiment 12 in accordancewith the present invention;

FIG. 24 is a diagram showing another example of displaying a no entrymark on the guide map in the navigation system of the embodiment 12 inaccordance with the present invention;

FIG. 25 is a flowchart showing the operation of a navigation system ofan embodiment 13 in accordance with the present invention;

FIG. 26 is a diagram showing an example of a guide map displayed in thenavigation system of the embodiment 13 in accordance with the presentinvention;

FIG. 27 is a flowchart showing the operation of a navigation system ofan embodiment 14 in accordance with the present invention;

FIG. 28 is a flowchart showing the operation of a navigation system ofan embodiment 15 in accordance with the present invention;

FIG. 29 is a flowchart showing the operation of a navigation system ofan embodiment 16 in accordance with the present invention;

FIG. 30 is a flowchart showing the operation of a navigation system ofan embodiment 17 in accordance with the present invention; and

FIG. 31 is a flowchart showing the operation of a navigation system ofan embodiment 18 in accordance with the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the invention will now be described withreference to the accompanying drawings to explain the present inventionin more detail.

Embodiment 1

A navigation system of an embodiment 1 in accordance with the presentinvention is configured in such a manner as to add informationrepresenting an HOV lane to a road number display during traveling inthe HOV lane.

FIG. 1 is a block diagram showing a hardware configuration of thenavigation system of the embodiment 1 in accordance with the presentinvention. The navigation system comprises an input device 11, a GPS(Global Positioning System) receiver 12, a distance sensor 13, adirection sensor 14, an occupant number sensor 15, a following vehicledetecting sensor 16, a map information storage 17, a display 18, a voiceoutput device 19 and a controller 20.

The input device 11 comprises a touch panel mounted on the screen of thedisplay 18, for example. The input device 11 is used for inputting astarting place, a destination or places passed through for a routesearch, or used for a user to provide the navigation system with avariety of instructions. The information input from the input device 11is delivered to the controller 20 as an operating signal.

The GPS receiver 12 detects the current position of the vehicle from GPSsignals received from GPS satellites. The current position of thevehicle detected by the GPS receiver 12 is delivered to the controller20 as a current position signal. The distance sensor 13 detects thedistance covered by the vehicle. The distance covered detected with thedistance sensor 13 is delivered to the controller 20 as a distancesignal. The direction sensor 14 detects the direction in which thevehicle faces. The direction detected with the direction sensor 14 isdelivered to the controller 20 as a direction signal.

The map information storage 17, which is constructed of an HDD (HardDisk Drive) system, for example, stores not only digitized mapinformation containing road data that define roads with links and nodes,but also various data for achieving navigation functions. Incidentally,the map information storage 17 can be constructed not only of the HDD,but also of a drive for reading data from a DVD (Digital VersatileDisk), CD (Compact Disk), memory stick or SD memory card, which areloaded.

A road represented by the road data contained in the map information isdefined by a single link regardless of whether an HOV lane is juxtaposedon the road or not. The link data representing a link includes HOV laneposition information indicating the position of an HOV lane, HOV lanepresence/absence information representing whether an HOV lane isjuxtaposed or not, lane change enabled position information representinga position at which a lane change is allowed between the HOV lane andanother lane, time regulation information representing apassable/impassable state of the HOV lane entrance/exit with respect totime, and the road name and road number. The road name is a name givento the road. The road number is the number given to the road. The datastored in the map information storage 17 are read by the controller 20.

The occupant number sensor 15 detects the number of passengers in avehicle. The number of the passengers detected with the occupant numbersensor 15 is delivered to the controller 20 as an occupant numbersignal. The following vehicle detecting sensor 16 detects thepresence/absence of a following vehicle in the lane which is adjacent tothe current driving lane and to which the lane is to be changed. Thepresence/absence of the following vehicle detected with the followingvehicle detecting sensor 16 is delivered to the controller 20 as afollowing vehicle signal.

The display 18, which is constructed of an LCD (Liquid Crystal Display),for example, displays a map, route, enlarged drawing, road number andvarious guiding messages on its screen in response to a video signaldelivered from the controller 20. The voice output device 19, whichconsists of a speaker, for example, outputs guide information such as aroad number, remaining distance or remaining time in voice in responseto the voice signal delivered from the controller 20.

The controller 20 controls the whole navigation system as will bedescribed in detail later. The controller 20 includes a CPU (CentralProcessing Unit) 21, a ROM (Read Only Memory) 22, a RAM (Random AccessMemory) 23, a display control unit 24 and an input/output control unit25.

The CPU 21, using the RAM 23 as a working memory, executes processingsuch as a route search or guide point extraction by operating accordingto programs read out of the ROM 22. The ROM 22 stores programs and datathat are read by the CPU 21 for executing various steps. The RAM 23,which is used as the working memory of the CPU 21 as mentioned above,temporarily stores data during processing (such as developed map data).

The display control unit 24 controls the display 18. More specifically,it converts the display data created by the CPU 21 to the video signal,and delivers it to the display 18 via the input/output control unit 25.The input/output control unit 25, which functions as an interfacebetween the controller 20 and the devices connected to it, that is, theinput device 11, GPS receiver 12, distance sensor 13, direction sensor14, occupant number sensor 15, following vehicle detecting sensor 16,map information storage 17, display 18 and voice output device 19,controls transfer of signals between them.

Next, functions achieved by the controller 20 will be described indetail. FIG. 2 is a functional block diagram showing a functionalconfiguration of the controller 20. The controller 20 includes a controlunit 30, a map information acquiring unit 31, a current positiondetecting unit 32, a following vehicle detecting unit 33, an occupantnumber detecting unit 34, a vehicle information extracting unit 35, aroute search unit 36, a route storage unit 37, an HOV lane decision unit38, an HOV lane entrance/exit extracting unit 39, a passable/impassabledecision unit 40, an HOV lane remaining time calculating unit 41, an HOVlane remaining distance calculating unit 42, a road number processingunit 43; a display processing unit 44, a voice message creating unit 45and a voice information unit 46. Among these units, those other than theroute storage 37 are implemented by program processing executed by theCPU 21.

The control unit 30 controls the controller 20 in its entirety. Forexample, the control unit 30 controls starting and stopping of thecomponents connected thereto and data transfer between the components.The map information acquiring unit 31 acquires map information from themap information storage 17 and delivers to the control unit 30.

The current position detecting unit 32 detects the current position ofthe vehicle from the current position signal delivered from the GPSreceiver 12 or the current position signal created by dead reckoningusing the direction signal delivered from the direction sensor 14 andthe distance signal delivered from the distance sensor 13, and the mapinformation acquired from the map information acquiring unit 31 via thecontrol unit 30. The current position detected by the current positiondetecting unit 32 is delivered to the control unit 30 as the currentposition information. Incidentally, since the data transfer between thecomponents connected to the control unit 30 is all performed via thecontrol unit 30, the description that it is performed via the controlunit 30 will be omitted below.

Even as for a road represented by a single link on the navigationsystem, the current position detecting unit 32 can detect in which laneof the single link it is traveling. The current position of the vehicledetected by the current position detecting unit 32 is delivered to thecontrol unit 30 as vehicle position information.

The following vehicle detecting unit 33 detects the presence/absence ofthe following vehicle from the following vehicle signal delivered fromthe following vehicle detecting sensor 16. The presence/absence of thefollowing vehicle detected by the following vehicle detecting unit 33 isdelivered to the control unit 30 as following vehicle data.Incidentally, as for a technique of detecting the following vehicle,since it is widely known and is disclosed in Japanese Patent Laid-OpenNos. 2004-268644, 2001-118197 and 11-245745/1999, for example, see themas necessary.

The occupant number detecting unit 34 detects the number of passengersin the vehicle from the occupant number signal delivered from theoccupant number sensor 15. The occupant number detected by the occupantnumber detecting unit 34 is delivered to the control unit 30 as occupantnumber data. Incidentally, as for a technique for detecting the occupantnumber, since it is well known and is disclosed in Japanese Patent No.3918326 and Japanese Patent Laid-Open No. 2005-061988, for example, seethem as necessary.

The vehicle information extracting unit 35 extracts, from the vehicle inwhich the navigation system is mounted, vehicle information about thevehicle such as information indicating the size of the vehicle. Thevehicle information extracted by the vehicle information extracting unit35 is delivered to the control unit 30.

The route search unit 36 searches for a route from the current positionindicated by the vehicle position information delivered from the currentposition detecting unit 32 or from the starting place input from theinput device 11 to the destination input from the input device 11 on thebasis of the map information acquired from the map information acquiringunit 31. The route searched by the route search unit 36 is delivered tothe route storage unit 37 as route data.

The route storage unit 37 is located, for example, in a portion of theRAM 23 of the controller 20 to store the route data delivered from theroute search unit 36. The route data stored in the route storage unit 37are read by the control unit 30.

The HOV lane decision unit 38 decides as to whether the HOV lane isincluded in a road contained in the map information acquired from themap information acquiring unit 31 or in a route stored in the routestorage unit 37. The decision result of the HOV lane decision unit 38 isdelivered to the control unit 30.

When the decision result acquired from the HOV lane decision unit 38indicates that the road or route includes the HOV lane, the HOV laneentrance/exit extracting unit 39 extracts an entrance/exit sectionbetween a lane other than the HOV lane and the HOV lane. Theentrance/exit section extracted by the HOV lane entrance/exit extractingunit 39 is delivered to the control unit 30 as entrance/exit positiondata.

According to the number of passengers indicated by the occupant numberdata delivered from the occupant number detecting unit 34 and thevehicle information delivered from the vehicle information extractingunit 35, the passable/impassable decision unit 40 decides whether theHOV lane of the road or route, as to which the HOV lane decision unit 38decides that it includes the HOV lane, is passable or not. The decisionresult by the passable/impassable decision unit 40 is delivered to thecontrol unit 30.

The HOV lane remaining time calculating unit 41 calculates the remainingtime of driving in the HOV lane of the road or route from the route datadelivered from the route storage unit 37, the decision result deliveredfrom the HOV lane decision unit 38, the entrance/exit position datadelivered from the HOV lane entrance/exit extracting unit 39 and thevehicle position information delivered from the current positiondetecting unit 32. The remaining time calculated by the HOV laneremaining time calculating unit 41 is delivered to the control unit 30as remaining time data.

The HOV lane remaining distance calculating unit 42 calculates theremaining distance of driving in the HOV lane of the road or route fromthe decision result delivered from the HOV lane decision unit 38, theentrance/exit position data delivered from the HOV lane entrance/exitextracting unit 39 and the vehicle position information delivered fromthe current position detecting unit 32. The remaining distancecalculated by the HOV lane remaining distance calculating unit 42 isdelivered to the control unit 30 as remaining distance data.

The road number processing unit 43 extracts the road number of the roadon the map or on the route in which the vehicle travels from the mapinformation delivered from the map information acquiring unit 31, thevehicle position information delivered from the current positiondetecting unit 32, the route data delivered from the route storage unit37 and the decision result delivered from the HOV lane decision unit 38,and processes the road number extracted in such a manner as to bedistinct as an HOV lane. The road number processed by the road numberprocessing unit 43 delivered to the control unit 30 as an HOV laneinformation added road number.

The display processing unit 44 forms the display data for displaying onthe display 18 the map expressed by the map information delivered fromthe map information acquiring unit 31, the route indicated by the routedata delivered from the route storage unit 37, the road including theHOV lane indicated by the decision result delivered from the HOV lanedecision unit 38, the entrance/exit position to the HOV lane indicatedby the entrance/exit position data delivered from the HOV laneentrance/exit extracting unit 39, an impassable road indicated by thedecision result delivered from the passable/impassable decision unit 40,the remaining time of driving in the HOV lane indicated by the remainingtime data delivered from the HOV lane remaining time calculating unit41, the remaining distance of driving in the HOV lane indicated by theremaining distance data delivered from the HOV lane remaining distancecalculating unit 42, and the HOV lane information added road numberdelivered from the road number processing unit 43. The display datagenerated by the display processing unit 44 is delivered to the displaycontrol unit 24 within the controller 20.

The voice message creating unit 45 forms voice messages for informing ofthe remaining time of driving in the HOV lane indicated by the remainingtime data delivered from the HOV lane remaining time calculating unit41, the remaining distance of driving in the HOV lane indicated by theremaining distance data delivered from the HOV lane remaining distancecalculating unit 42, the HOV lane information added road numberdelivered from the road number processing unit 43, the route indicatedby the route data delivered from the route storage unit 37, the roadincluding the HOV lane indicated by the decision result delivered fromthe HOV lane decision unit 38, and whether a lane change to and from theHOV lane is possible or not which is decided from the entrance/exitposition to the HOV lane indicated by the entrance/exit position datadelivered from the HOV lane entrance/exit extracting unit 39 and thepresence/absence of the following vehicle indicated by the followingvehicle data delivered from the following vehicle detecting unit 33. Thevoice messages generated by the voice message creating unit 45 aredelivered to the voice information unit 46 as the voice data.

The voice information unit 46 converts the voice data delivered from thevoice message creating unit 45 to a voice signal, and delivers to thevoice output device 19. Thus, the voice information corresponding to thevoice message is output from the voice output device 19.

Next, the operation of the navigation system of the embodiment 1 inaccordance with the present invention with the foregoing configurationwill be described with reference to the flowchart shown in FIG. 3centering on the road number information processing for guiding byadding to the road number the information indicating that it has an HOVlane.

In the road number information processing, the map information isacquired, first (step ST11). More specifically, the control unit 30acquires the map information from the map information storage 17 via themap information acquiring unit 31, and delivers to the HOV lane decisionunit 38. Subsequently, the map information acquired is checked whetherit includes an HOV lane or not (step ST12). More specifically, the HOVlane decision unit 38 decides whether the road indicated by the mapinformation delivered from the control unit 30 includes the HOV lane ornot, and delivers the decision result to the control unit 30.

If a decision is made that the HOV lane is located at this step ST12,then the HOV lane position is acquired (step ST13). More specifically,when the decision result that the HOV lane is included is delivered fromthe HOV lane decision unit 38, the control unit 30 acquires the HOV laneposition from the HOV lane position information in the link datacorresponding to the road including the HOV lane.

Subsequently, the road number of the HOV lane is acquired (step ST14).More specifically, the control unit 30 acquires the road number of thelink data corresponding to the road including the HOV lane and deliversto the road number processing unit 43. Subsequently, the road number isprocessed (step ST15). More specifically, the road number processingunit 43 processes the road number delivered from the control unit 30 insuch a manner as to become distinct as the HOV lane, and delivers to thecontrol unit 30 as the HOV lane information added road number. Afterthat, the sequence proceeds to step ST17.

If a decision is made at the foregoing step ST12 that no HOV lane islocated, then the road number is acquired (step ST16). Morespecifically, the control unit 30 acquires the road number of the linkdata corresponding to the road without an HOV lane. After that, thesequence proceeds to step ST17.

At step ST17, information is given through at least one of the roadnumber display or voice output. More specifically, the control unit 30delivers the HOV lane information added road number delivered from theroad number processing unit 43 at step ST15 or the road number acquiredat step ST16 to at least one of the display processing unit 44 and thevoice message creating unit 45.

When receiving the HOV lane information added road number or road numberfrom the control unit 30, the display processing unit 44 creates thedisplay data to display it, and delivers to the display control unit 24in the controller 20. The display control unit 24 converts the displaydata delivered from the display processing unit 44 to a video signal,and delivers to the display 18 via the input/output control unit 25.This enables the display 18 to display the HOV lane information addedroad number or road number on its screen.

The HOV lane information added road number can be displayed in variousmodes that make it clear that it indicates the road number of the HOVlane. FIG. 4 to FIG. 6 are diagrams showing examples that display theHOV lane information added road number on the screen of the display 18.FIG. 4 is an example which displays the road number “22” with a mark(diamond shape) representing an HOV lane when displaying the road numberin an information display area about a forward guide point.

FIG. 5 is an example which displays the road number “CA-22 E” with amark (diamond shape) representing an HOV lane when displaying the roadnumber in a current driving road information display area (at the bottomof the screen). FIG. 6 is an example which displays the road number“I-110-HOV-LN” to which “HOV-LN” representing an HOV lane is added whendisplaying the road number in the information display area of theforward guide point.

In addition, when the HOV lane information added road number or roadnumber is delivered from the control unit 30, the voice message creatingunit 45 forms a voice message for outputting them in voice, and deliversto the voice information unit 46 as voice data. The voice informationunit 46 converts the voice data delivered from the voice messagecreating unit 45 to a voice signal, and delivers to the voice outputdevice 19. This enables the voice output device 19 to output the voiceinformation corresponding to the HOV lane information added road numberor road number. After that, the road number information processing isterminated.

As described above, according to the navigation system of the embodiment1 in accordance with the present invention, since it displays a stringor figure representing the HOV lane in the road number display duringdriving in the HOV lane, it can cause a user to visually perceive inwhich road the user is driving. In addition, since the messageindicating the HOV lane is added to the road number and is output invoice during driving in the HOV lane, it can cause the user toauditorily perceive in which road the user is driving.

Embodiment 2

The navigation system of an embodiment 2 in accordance with the presentinvention is configured in such a manner that while driving in the HOVlane, it adds information representing an HOV lane to a road numberdisplay and outputs, and that even if the link data representing a roaddoes not contain the road number, in particular, it extracts the roadnumber from the road name, adds the information representing the HOVlane to the road number it extracts, and displays it.

The configuration of the navigation system of the embodiment 2 inaccordance with the present invention is the same as that of thenavigation system of the foregoing embodiment 1. The followingdescription will be made centering on differences (in operation) fromthe navigation system of the embodiment 1.

As for an HOV dedicated lane (HOV dedicated road), there are some caseswhere a link representing the road does not contain its road number, butcontains only its road name. In addition, as for the road number, thereare some cases where it is stored in the road name in the form like aroad number. The following are examples of storing formats of a roadname and road number concerning an HOV lane.

(a) HOV Dedicated Lane (HOV Dedicated Road)

-   -   Example 1 (WEST SIDE of LOS ANGELES)        -   Road Name: I-110-HOV-LN        -   Road Number Unavailable    -   Example 2 (NORTHERN PART of LOS ANGELES)        -   Road Name: BUS LN        -   Road Number Unavailable    -   Example 3 (NORTHERN PART of I-95N)        -   Road Name: Unavailable        -   Road Number: I-395 HOV LN

(b) Mixed Road of HOV Lane and FWY (Freeway) Lane

-   -   Example 1 (EAST SIDE of LOS ANGELES)        -   Road Name: Unavailable        -   Road Number: I-110 N    -   Example 2 (WEST SIDE of LOS ANGELES)        -   Road Name: Unavailable        -   Road Number: I-405 N

(c) Road with Only FWY Lane

-   -   Example 1 (NORTHERN PART of LOS ANGELES)        -   Road Name: Unavailable        -   Road Number: I-10 W    -   Example 2        -   Road Name: (EAST SIDE of BROOKLYN)        -   Road Number: I-278 E

Next, the road number information processing corresponding to the caseswith the foregoing storage formats of the road names and road numberswill be described with reference to the flowchart of FIG. 7.Incidentally, as for the steps for executing the same or like processingto the processing shown in the flowchart of FIG. 3, they are designatedby the same symbols as those of FIG. 3, and their description will beomitted for simplification.

In the road number information processing, the map information isacquired, first (step ST11). Subsequently, the map information acquiredis checked whether it has an HOV lane or not (step ST12). At this stepST12, if a decision is made that the HOV lane is not located, then theroad number is acquired (step ST16). After that, the sequence proceedsto step ST17.

If a decision is made at the foregoing step ST12 that the HOV lane isincluded, then the HOV lane position is acquired (step ST13).Subsequently, the road number of the HOV lane is acquired (step ST14).More specifically, the control unit 30 tries to acquire the road numberof the link data corresponding to the road including the HOV lane.

Subsequently, it is checked whether the road number is stored or not(step ST21). More specifically, the control unit 30 checks whether thelink data acquired at step ST14 contains the road number or not. If adecision is made at this step ST21 that the road number is contained,the control unit 30 delivers the road number to the road numberprocessing unit 43. After that, the sequence proceeds to step ST17.

On the other hand, unless a decision is made at step ST21 that the roadnumber is contained, then the road name of the HOV lane is acquired(step ST22). More specifically, the control unit 30 acquires the roadname of the link data corresponding to the road including the HOV lane.

Subsequently, it is checked whether the road name contains the roadnumber or not (step ST23). More specifically, the control unit 30 checkswhether the road name contained in the link data acquired at step ST22contains the road number or not. In the processing, the control unit 30extracts the road number from the road name, first. An example of theprocessing of extracting the road number from the road name will bedescribed.

First, a numeric part is cut out. More specifically, the string of thenumeric part and its position are identified in the road name.Subsequently, the road number is identified. More specifically, a stringat the preceding position of the numeric part cut out is checked whetherit agrees with a string shown in FIG. 8 or not, for example, and when itagrees, the numeral is handled as a part of the road number. Unless itagrees, it is not handled as a part of the road number. Incidentally,the letters shown in FIG. 8 are prefixes making a pair with thenumerals, and the road number consists of a combination of the numeraland the prefix. In the following, two concrete examples will bedescribed.

For example, when the road name is “Freeway I-95”, the numeric part “95”is cut out, first, followed by a decision that the numeral is located at11th position and after. Subsequently, the string just before the 11thletter is decided whether it agrees with a string shown in FIG. 8 ornot. In this case, since it agrees with “I-”, “I-95” is extracted anddecided as a road number.

For example, when the road name is “Freeway Exit5”, the numeric part “5”is cut out, first, followed by a decision that the numeral is located at13th position and after. Subsequently, the string just before the 13thletter is decided whether it agrees with a string shown in FIG. 8. Inthis case, since no string agrees, a decision is made that the roadnumber is not present.

If a decision is made at the foregoing step ST23 that the road name doesnot contain the road number, the road number cannot be acquired. Thus,the road number information processing is terminated without guidance ofthe road number. On the other hand, if a decision is made at step ST23that the road name contains the road number, the sequence proceeds tostep ST17.

At step ST17, information is given by means of at least one of thedisplay and voice output of the road number. More specifically, thecontrol unit 30 delivers the road number acquired at step ST14 or theroad number extracted at step ST23 to at least one of the displayprocessing unit 44 and voice message creating unit 45.

When the road numbers are delivered from the control unit 30, thedisplay processing unit 44 forms the display data for displaying them,and delivers to the display control unit 24 within the controller 20.The display control unit 24 converts the display data delivered from thedisplay processing unit 44 to the video signal, and delivers to thedisplay 18 via the input/output control unit 25. Thus, the road numberis displayed on the screen of the display 18.

As described above, according to the navigation system of the embodiment2 in accordance with the present invention, it is configured in such amanner that it tries to acquire both the road name and road numberbecause as for the HOV dedicated lane (HOV dedicated road), there aremany cases where it stores only the road name without storing the roadnumber and there are some cases where the road name contains the roadnumber, and that if one of the road name and road number contains a partcapable of being informed as the road number, it extracts the roadnumber and displays and outputs in voice. Accordingly, it can giveinformation about the road number even as to the road that contains onlythe road name. As a result, it can cause a user to recognize the drivingroad or the road ahead (next driving road) more easily than when itgives information about the road name that is generally longer than theroad number.

Embodiment 3

The navigation system of the present embodiment 3 is one that has boththe functions of the navigation system of the foregoing embodiment 1 andthe functions of the navigation system of the embodiment 2. Theconfiguration of the navigation system of the embodiment 3 in accordancewith the present invention is the same as that of the navigation systemof the foregoing embodiment 2. The following description will be madecentering on differences (in operation) from the navigation system ofthe embodiment 2.

FIG. 9 is a flowchart showing the operation of the navigation system ofthe embodiment 3 centering on the road number information processing.Incidentally, in the flowchart shown in FIG. 9, steps executing the sameor like processing to the processing in the flowchart shown in FIG. 3and FIG. 7 are designated by the same symbols as those of FIG. 3 andFIG. 7 to simplify the explanation.

In the road number information processing, the map information isacquired, first (step ST11). Subsequently, it is checked whether the mapinformation acquired contains an HOV lane or not (step ST12). At thisstep ST12, if a decision is made that no HOV lane is located, then theroad number is acquired (step ST16). After that, the sequence proceedsto step ST17.

In the foregoing step ST12, if a decision is made that the HOV lane iscontained, then the HOV lane position is acquired (step ST13).Subsequently, the road number of the HOV lane is acquired (step ST14).Subsequently, it is checked whether the road number is stored or not(step ST21). At this step ST21, if a decision is made that the roadnumber is contained, the sequence proceeds to step ST15.

On the other hand, if a decision is made at step ST21 that the roadnumber is not contained, then the road name of the HOV lane is acquired(step ST22). Subsequently, it is checked whether the road name containsthe road number or not (step ST23). At this step ST23, if a decision ismade that the road name does not contain the road number, the roadnumber cannot be obtained. Accordingly, the road number informationprocessing is terminated without giving information on the road number.On the other hand, if a decision is made at step ST23 that the road namecontains the road number, then the sequence proceeds to step ST15.

At step ST15, the road number is processed. More specifically, the roadnumber processing unit 43 processes the road number delivered from thecontrol unit 30 as a result of the processing at step ST21 or step ST23in such a manner as to enable a user to recognize as the HOV lane, anddelivers to the control unit 30 as the HOV lane information added roadnumber. After that, the sequence proceeds to step ST17.

At step ST17, the information is given by means of at least one of theroad number display and voice output. More specifically, the controlunit 30 delivers the HOV lane information added road number deliveredfrom the road number processing unit 43 at step ST15 or the road numberacquired at step ST16 to at least one of the display processing unit 44and voice message creating unit 45.

Thus, the HOV lane information added road number or road number isdisplayed on the screen of the display 18. In addition, the voice outputdevice 19 outputs the voice information corresponding to the HOV laneinformation added road number or road number. After that, the roadnumber information processing is terminated.

As described above, according to the navigation system of the embodiment3 in accordance with the present invention, it offers combinedadvantages of the advantages of the navigation system of the foregoingembodiment 1 and the advantages of the navigation system of theembodiment 2.

Embodiment 4

The navigation system of the embodiment 4 in accordance with the presentinvention is configured in such a manner as to give information aboutthe remaining distance of an HOV lane change enabled section by displayduring driving in the HOV lane. The configuration of the navigationsystem of the embodiment 4 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 1.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 1.

FIG. 10 is a flowchart showing the operation of the navigation system ofthe embodiment 4 centering on the remaining distance informationprocessing. In the remaining distance information processing, the mapinformation is acquired, first (step ST31). More specifically, thecontrol unit 30 acquires the map information from the map informationstorage 17 via the map information acquiring unit 31, and delivers tothe route search unit 36. Subsequently, the vehicle position informationis acquired (step ST32). More specifically, the control unit 30 acquiresthe vehicle position information from the current position detectingunit 32, and delivers to the route search unit 36.

Subsequently, a route search is carried out (step ST33). Morespecifically, the route search unit 36, considering the current positionindicated by the vehicle position information delivered from the currentposition detecting unit 32 at step ST32 as a starting place, searchesfor a route to the destination input through the input device 11 fromthe map information acquired from the map information acquiring unit 31at step ST31. The route searched by the route search unit 36 isdelivered to the route storage unit 37 as the route data.

Subsequently, it is checked whether the route has an HOV lane or not(step ST34). More specifically, the HOV lane decision unit 38 acquiresthe route data from the route storage unit 37, and decides whether theroute indicated by the route data includes an HOV lane or not. Thedecision result of the HOV lane decision unit 38 is delivered to thecontrol unit 30. If a decision is made at this step ST34 that no HOVlane is located on the route, the HOV lane change enabled section doesnot exist. Thus, the remaining distance information processing isterminated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether the HOV lane changeenabled section is located or not (step ST35). More specifically, whenthe decision result acquired from the HOV lane decision unit 38indicates that the route includes the HOV lane, the control unit 30acquires lane change enabled position information indicating theposition where a lane change is allowed between the HOV lane and anotherlane from the link data corresponding to the HOV lane. If a decision ismade at this step ST35 that the HOV lane change enabled section is notpresent, the remaining distance information processing is terminated.

On the other hand, if a decision is made at step ST35 that the HOV lanechange enabled section is located, the HOV lane change enabled sectionposition is acquired (step ST36). More specifically, the control unit 30acquires the HOV lane change enabled section position from the lanechange enabled position information acquired at step ST35.

Subsequently, it is checked whether the vehicle is driving in the HOVlane change enabled section or not (step ST37). More specifically, thecontrol unit 30 checks whether the current position detected with thecurrent position detecting unit 32 is located in the HOV lane changeenabled section acquired at step ST36 or not. If a decision is made atthis step ST37 that the vehicle is not traveling in the HOV lane changeenabled section, it enters a standby mode in which this step ST37 isexecuted repeatedly.

If a decision is made that the vehicle is traveling in the HOV lanechange enabled section in the standby mode in which this step ST37 isexecuted repeatedly, then the information about the remaining distancefrom the vehicle position to the endpoint of the HOV lane change enabledsection is given by display (step ST38). More specifically, the HOV laneremaining distance calculating unit 42 calculates the remaining distanceto be covered in the HOV lane change enabled section from theentrance/exit position data delivered from the HOV lane entrance/exitextracting unit 39 and the vehicle position information delivered fromthe current position detecting unit 32, and delivers to the displayprocessing unit 44 as the remaining distance data.

The display processing unit 44 creates the display data for causing thedisplay 18 to display the remaining distance to be covered in the HOVlane indicated by the remaining distance data delivered from the HOVlane remaining distance calculating unit 42, and delivers to the displaycontrol unit 24 within the controller 20. The display control unit 24converts the display data received to the video signal and delivers tothe display 18 via the input/output control unit 25. Thus, the remainingdistance from the vehicle position to the endpoint of the HOV lanechange enabled section is displayed on the guide map displayed on thedisplay 18 as shown in FIG. 11.

Subsequently, it is checked whether the vehicle has passed through theendpoint of the HOV lane change enabled section or not (step ST39). Morespecifically, the control unit 30 checks whether the current positiondetected by the current position detecting unit 32 is located in the HOVlane change enabled section acquired at step ST36 or not. If a decisionis made at this step ST39 that the vehicle has not yet passed throughthe endpoint of the HOV lane change enabled section, the sequencereturns to step ST38 to repeat the foregoing processing. Thus, theremaining distance displayed on the guide map displayed on the display18 changes every moment in accordance with the driving.

On the other hand, if a decision is made at step ST39 that the vehiclehas passed through the endpoint of the HOV lane change enabled section,the sequence returns to step ST35 to repeat the foregoing processing.Thus, the processing is executed for the next HOV lane change enabledsection on the HOV lane.

As described above, according to the navigation system of the embodiment4 in accordance with the present invention, it is configured in such amanner that while the vehicle is traveling in the HOV lane changeenabled section, it gives information about the remaining distance tothe endpoint of the HOV lane change enabled section by displaying it.Accordingly, the user can recognize in advance a place as far as which alane change has to be done, thereby being able to change the lane at theuser's timing.

Embodiment 5

The navigation system of an embodiment 5 in accordance with the presentinvention is configured in such a manner as to inform the user of theremaining distance of the HOV lane change enabled section in voiceduring traveling in the HOV lane. The configuration of the navigationsystem of the embodiment 5 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 4.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 4.

FIG. 12 is a flowchart showing the operation of the navigation system ofthe embodiment 5 centering on the remaining distance informationprocessing. Incidentally, steps executing the same or like processing tothe processing in the flowchart shown in FIG. 10 are designated by thesame symbols as those of FIG. 10 to simplify the explanation.

In the remaining distance information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located on the route, the remaining distanceinformation processing is terminated because no HOV lane change enabledsection is located.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether the HOV lane changeenabled section is located or not (step ST35). If a decision is made atthis step ST35 that no HOV lane change enabled section is located, theremaining distance information processing is terminated.

On the other hand, if a decision is made at step ST35 that the HOV lanechange enabled section is located, the HOV lane change enabled sectionposition is acquired (step ST36). Subsequently, it is checked whetherthe vehicle is traveling in the HOV lane change enabled section or not(step ST37). If a decision is made at this step ST37 that the vehicle isnot traveling in the HOV lane change enabled section, it enters astandby mode in which this step ST37 is executed repeatedly.

If a decision is made that the vehicle is traveling in the HOV lanechange enabled section in the standby mode in which this step ST37 isexecuted repeatedly, then the information about the remaining distancefrom the vehicle position to the endpoint of the HOV lane change enabledsection is output in voice (step ST41). More specifically, the HOV laneremaining distance calculating unit 42 calculates the remaining distanceto be covered in the HOV lane change enabled section of the route fromthe entrance/exit position data delivered from the HOV laneentrance/exit extracting unit 39 and the vehicle position informationdelivered from the current position detecting unit 32, and delivers tothe voice message creating unit 45 as the remaining distance data.

The voice message creating unit 45 forms a voice message for guidance ofthe remaining distance to be covered in the HOV lane indicated by theremaining distance data delivered from the HOV lane remaining distancecalculating unit 42, and delivers to the voice information unit 46 asthe voice data. The voice information unit 46 converts the voice datadelivered from the voice message creating unit 45 to the voice signal,and delivers it to the voice output device 19. The voice output device19 outputs the voice information indicating the remaining distance tothe endpoint of the HOV lane change enabled section.

Subsequently, it is checked whether the vehicle has passed through theendpoint of the HOV lane change enabled section or not (step ST39). If adecision is made at this step ST39 that the vehicle has not yet passedthrough the endpoint of the HOV lane change enabled section, thesequence returns to step ST41 to repeat the foregoing processing. Thus,the remaining distance output from the voice output device 19 changesevery moment in accordance with the driving.

On the other hand, if a decision is made at step ST39 that the vehiclehas passed through the endpoint of the HOV lane change enabled section,the sequence returns to step ST35 to repeat the foregoing processing.Thus, the processing is executed for the next HOV lane change enabledsection on the HOV lane.

As described above, according to the navigation system of the embodiment5 in accordance with the present invention, it is configured in such amanner that while the vehicle is traveling in the HOV lane changeenabled section, it gives information about the remaining distance tothe endpoint of the HOV lane change enabled section in voice.Accordingly, the user can recognize in advance a place as far as which alane change has to be done, thereby being able to change the lane at theuser's timing.

Embodiment 6

The navigation system of the embodiment 6 in accordance with the presentinvention is configured in such a manner as to give information aboutthe remaining time of an HOV lane change enabled section by displayduring driving in the HOV lane. The configuration of the navigationsystem of the embodiment 6 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 4.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 4.

FIG. 13 is a flowchart showing the operation of the navigation system ofthe embodiment 6 centering on the remaining time information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 10 are designated by the samesymbols as those of FIG. 10 to simplify the explanation.

In the remaining time information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located on the route, the remaining time informationprocessing is terminated because no HOV lane change enabled section islocated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether the HOV lane changeenabled section is located or not (step ST35). If a decision is made atthis step ST35 that no HOV lane change enabled section is located, theremaining time information processing is terminated.

On the other hand, if a decision is made at step ST35 that the HOV lanechange enabled section is located, the HOV lane change enabled sectionposition is acquired (step ST36). Subsequently, it is checked whetherthe vehicle is traveling in the HOV lane change enabled section or not(step ST37). If a decision is made at this step ST37 that the vehicle isnot traveling in the HOV lane change enabled section, it enters astandby mode in which this step ST37 is executed repeatedly.

If a decision is made that the vehicle is traveling in the HOV lanechange enabled section in the standby mode in which this step ST37 isexecuted repeatedly, then the information about the remaining time fromthe vehicle position to the endpoint of the HOV lane change enabledsection is given by display (step ST51). More specifically, the HOV laneremaining time calculating unit 41 calculates the remaining time oftraveling in the HOV lane change enabled section from the entrance/exitposition data delivered from the HOV lane entrance/exit extracting unit39 and the vehicle position information delivered from the currentposition detecting unit 32, and delivers to the display processing unit44 as the remaining time data. The display processing unit 44 createsthe display data for causing the display 18 to display the remainingtime of traveling the HOV lane indicated by the remaining time datadelivered from the HOV lane remaining time calculating unit 41, anddelivers to the display control unit 24 within the controller 20. Thedisplay control unit 24 converts the display data received to the videosignal and delivers to the display 18 via the input/output control unit25. Thus, as shown in FIG. 11, the remaining time from the vehicleposition to the endpoint of the HOV lane change enabled section isdisplayed on the guide map displayed on the display 18.

Subsequently, it is checked whether the vehicle has passed through theendpoint of the HOV lane change enabled section or not (step ST39). If adecision is made at this step ST39 that the vehicle has not yet passedthrough the endpoint of the HOV lane change enabled section, thesequence returns to step ST51 to repeat the foregoing processing. Thus,the remaining time on the guide map displayed on the display 18 changesevery moment in accordance with the driving.

On the other hand, if a decision is made at step ST39 that the vehiclehas passed through the endpoint of the HOV lane change enabled section,the sequence returns to step ST35 to repeat the foregoing processing.Thus, the processing is executed for the next HOV lane change enabledsection on the HOV lane.

As described above, according to the navigation system of the embodiment6 in accordance with the present invention, it is configured in such amanner that while the vehicle is traveling in the HOV lane changeenabled section, it gives information about the remaining time to theendpoint of the HOV lane change enabled section by displaying it.Accordingly, the user can recognize in advance a place as far as which alane change has to be done, thereby being able to change the lane at theuser's timing.

Embodiment 7

The navigation system of an embodiment 7 in accordance with the presentinvention is configured in such a manner as to give information aboutthe remaining time of the HOV lane change enabled section in voiceduring traveling in the HOV lane. The configuration of the navigationsystem of the embodiment 7 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 4.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 4.

FIG. 14 is a flowchart showing the operation of the navigation system ofthe embodiment 7 centering on the remaining time information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 10 are designated by the samesymbols as those of FIG. 10 to simplify the explanation.

In the remaining time information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located on the route, the remaining time informationprocessing is terminated because no HOV lane change enabled section islocated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether the HOV lane changeenabled section is located or not (step ST35). If a decision is made atthis step ST35 that no HOV lane change enabled section is located, theremaining time information processing is terminated.

On the other hand, if a decision is made at step ST35 that the HOV lanechange enabled section is located, the HOV lane change enabled sectionposition is acquired (step ST36). Subsequently, it is checked whetherthe vehicle is traveling in the HOV lane change enabled section or not(step ST37). If a decision is made at this step ST37 that the vehicle isnot traveling in the HOV lane change enabled section, it enters astandby mode in which this step ST37 is executed repeatedly.

If a decision is made that the vehicle is traveling in the HOV lanechange enabled section in the standby mode in which this step ST37 isexecuted repeatedly, then the information about the remaining time fromthe vehicle position to the endpoint of the HOV lane change enabledsection is output in voice (step ST61). More specifically, the HOV laneremaining time calculating unit 41 calculates the remaining time oftraveling in the HOV lane change enabled section of the route from theentrance/exit position data delivered from the HOV lane entrance/exitextracting unit 39 and the vehicle position information delivered fromthe current position detecting unit 32, and delivers to the voicemessage creating unit 45 as the remaining time data.

The voice message creating unit 45 forms a voice message for guidance ofthe remaining time of traveling in the HOV lane indicated by theremaining time data delivered from the HOV lane remaining timecalculating unit 41, and delivers to the voice information unit 46 asthe voice data. The voice information unit 46 converts the voice datadelivered from the voice message creating unit 45 to the voice signal,and delivers it to the voice output device 19. Thus, the voice outputdevice 19 outputs the voice information indicating the remaining timefor passing through the endpoint of the HOV lane change enabled section.

Subsequently, it is checked whether the vehicle has passed through theendpoint of the HOV lane change enabled section or not (step ST39). If adecision is made at this step ST39 that the vehicle has not yet passedthrough the endpoint of the HOV lane change enabled section, thesequence returns to step ST61 to repeat the foregoing processing. Thus,the remaining time output from the voice output device 19 changes everymoment in accordance with the driving.

On the other hand, if a decision is made at step ST39 that the vehiclehas passed through the endpoint of the HOV lane change enabled section,the sequence returns to step ST35 to repeat the foregoing processing.Thus, the processing is executed for the next HOV lane change enabledsection on the HOV lane.

As described above, according to the navigation system of the embodiment7 in accordance with the present invention, it is configured in such amanner that while the vehicle is traveling in the HOV lane changeenabled section, it gives information about the remaining time to theendpoint of the HOV lane change enabled section in voice. Accordingly,the user can recognize in advance a place as far as which a lane changehas to be done, thereby being able to change the lane at the user'stiming.

Incidentally, although the navigation systems of the foregoingembodiment 4 to embodiment 7 are configured in such a manner as to giveinformation about the remaining distance or remaining time duringdriving in the HOV lane on the route obtained by the route search, aconfiguration is also possible which gives information about theremaining distance or remaining time when a route is not present, orwhen driving in an ordinary lane though the route is located.

Embodiment 8

The navigation system of an embodiment 8 in accordance with the presentinvention is configured in such a manner as to display an entrance/exitbetween an HOV lane and another lane as a guide section mark. Theconfiguration of the navigation system of the embodiment 8 in accordancewith the present invention is the same as that of the navigation systemof the foregoing embodiment 4. The following description will be madecentering on differences (in operation) from the navigation system ofthe embodiment 4.

FIG. 15 is a flowchart showing the operation of the navigation system ofthe embodiment 8 centering on the entrance/exit information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 10 are designated by the samesymbols as those of FIG. 10 to simplify the explanation.

In the entrance/exit information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located on the route, the entrance/exit informationprocessing is terminated because no HOV lane entrance/exit is placed.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether an entrance/exitbetween the HOV lane and another lane is placed on the HOV lane or not(step ST71). More specifically, the HOV lane entrance/exit extractingunit 39 extracts, when the decision result acquired from the HOV lanedecision unit 38 indicates that the route includes the HOV lane, anentrance/exit section between the lanes other than the HOV lane and theHOV lane, and delivers to the control unit 30. If a decision is made atthis step ST71 that the entrance/exit between the HOV lane and anotherlane is not placed on the HOV lane, the entrance/exit informationprocessing is terminated.

On the other hand, if a decision is made at step ST71 that theentrance/exit is placed between the HOV lane and another lane on the HOVlane, an HOV lane entrance/exit section position is acquired (stepST72). More specifically, the control unit 30 acquires, when theentrance/exit position data is delivered from the HOV lane entrance/exitextracting unit 39, the section indicated by the entrance/exit positiondata as the HOV lane entrance/exit section position.

Subsequently, a guide section mark is displayed in the entrance/exitsection between the HOV lane and another lane in a part of the HOV laneon the route on the guide map (step ST73). More specifically, thecontrol unit 30 delivers the HOV lane entrance/exit section positionacquired at step ST72 to the display processing unit 44. The displayprocessing unit 44 creates display data for causing the display 18 todisplay the HOV lane entrance/exit section position delivered from thecontrol unit 30 as the guide section mark, and delivers to the displaycontrol unit 24 within the controller 20. The display control unit 24converts the display data received to the video signal, and delivers tothe display 18 via the input/output control unit 25. Thus, the guidesection mark as shown in FIG. 16 is displayed in the entrance/exitsection between the HOV lane and another lane on the guide map displayedon the display 18.

As described above, according to the navigation system of the embodiment8 in accordance with the present invention, since it is configured insuch a manner as to display the guide section mark in the entrance/exitsection to make the entrance/exit section of the HOV lane distinct onthe guide map, the user can recognize that he or she is approaching aplace of entry and departure and that which place on the route he or sheshould enter or exit.

Embodiment 9

The navigation system of an embodiment 9 in accordance with the presentinvention is configured in such a manner as to display the guide sectionmark indicating an entrance/exit between the HOV lane and another lanein different shapes in accordance with the time regulation. Theconfiguration of the navigation system of the embodiment 9 in accordancewith the present invention is the same as that of the navigation systemof the foregoing embodiment 8. The following description will be madecentering on differences (in operation) from the navigation system ofthe embodiment 8.

FIG. 17 is a flowchart showing the operation of the navigation system ofthe embodiment 9 centering on the entrance/exit information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 15 are designated by the samesymbols as those of FIG. 15 to simplify the explanation.

In the entrance/exit information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located on the route, the entrance/exit informationprocessing is terminated because no HOV lane entrance/exit is placed.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether an entrance/exitbetween the HOV lane and another lane is placed on the HOV lane (stepST71). More specifically, the HOV lane entrance/exit extracting unit 39extracts, when the decision result acquired from the HOV lane decisionunit 38 indicates that the route includes the HOV lane, an entrance/exitsection between the lanes other than the HOV lane and the HOV lane, anddelivers to the control unit 30 as an entrance/exit position data. If adecision is made at this step ST71 that the entrance/exit between theHOV lane and another lane is not placed on the HOV lane, theentrance/exit information processing is terminated.

On the other hand, if a decision is made at step ST71 that theentrance/exit is placed between the HOV lane and another lane on the HOVlane, the HOV lane entrance/exit section position is acquired (stepST72). More specifically, the control unit 30 acquires, when theentrance/exit position data is delivered from the HOV lane entrance/exitextracting unit 39, the section indicated by the entrance/exit positiondata as the HOV lane entrance/exit section position.

Subsequently, it is checked whether the HOV lane entrance/exit ispassable or not according to the time regulation (step ST81). Morespecifically, the control unit 30 acquires from the link datacorresponding to the HOV lane the time regulation information indicatinga passable/impassable state of the HOV lane entrance/exit in accordancewith time, and checks whether the HOV lane entrance/exit is passable atthat time.

If a decision is made at this step ST81 that the HOV lane entrance/exitis passable according to the time regulation, a passable guide sectionmark is displayed in the entrance/exit section between the HOV lane andanother lane on the guide map (step ST82). More specifically, thecontrol unit 30 delivers the HOV lane entrance/exit section positionacquired at step ST72 to the display processing unit 44. The displayprocessing unit 44 forms the display data for causing the display 18 todisplay the HOV lane entrance/exit section position delivered from thecontrol unit 30 as the passable guide section mark, and delivers to thedisplay control unit 24 within the controller 20. The display controlunit 24 converts the display data received to the video signal, anddelivers to the display 18 via the input/output control unit 25. Thus,the guide section mark is displayed in the entrance/exit section betweenthe HOV lane and another lane on the guide map displayed on the display18.

On the other hand, if a decision is made at step ST81 that the HOV laneentrance/exit is impassable according to the time regulation, animpassable guide section mark is displayed in the entrance/exit sectionbetween the HOV lane and another lane on the guide map (step ST83). Morespecifically, the control unit 30 delivers the HOV lane entrance/exitsection position acquired at step ST72 to the display processing unit44. The display processing unit 44 forms the display data for causingthe display 18 to display the HOV lane entrance/exit section positiondelivered from the control unit 30 as the impassable guide section mark,and delivers to the display control unit 24 within the controller 20.The display control unit 24 converts the display data received to thevideo signal and delivers to the display 18 via the input/output controlunit 25. Thus, the impassable guide section mark is displayed in theentrance/exit section between the HOV lane and another lane on the guidemap displayed on the display 18.

As for the foregoing passable guide section mark and the impassableguide section mark, they can be formed in such a manner as to havedifferent designs, colors, shapes or brightness.

As described above, according to the navigation system of the embodiment9 in accordance with the present invention, since it is configured insuch a manner as to display the guide section mark of the entrance/exitdisplayed on the guide map in different designs, colors, shapes orbrightness in accordance with the passable/impassable state of the HOVlane entrance/exit according to the time regulation, the user can decidethe passableness of the entrance/exit section visually.

Embodiment 10

The navigation system of an embodiment 10 in accordance with the presentinvention is configured in such a manner as to give information aboutthe HOV lane that is decided to be impassable according to regulation asa no entry road. The configuration of the navigation system of theembodiment 10 in accordance with the present invention is the same asthat of the navigation system of the foregoing embodiment 1. Thefollowing description will be made centering on differences (inoperation) from the navigation system of the embodiment 1.

FIG. 18 is a flowchart showing the operation of the navigation system ofthe embodiment 10. Here, an example will be described which is regulatedaccording to the number of passengers.

First, it is checked whether only one passenger is traveling in thevehicle or not (step ST91). More specifically, the passable/impassabledecision unit 40 checks whether the number of passengers indicated bythe occupant number data delivered from the occupant number detectingunit 34 is one or not. If a decision is made at this step ST91 that onlyone passenger is traveling in the vehicle, then the HOV lane is handledas an ordinary no entry road (step ST92). More specifically, the controlunit 30 controls in such a manner as to inform about the HOV lane as ano entry road. After that, the processing is terminated.

On the other hand, if a decision is made at step ST91 that a pluralityof passengers are in the vehicle rather than one, then the guidanceassociated with the HOV lane is performed (step ST93). Morespecifically, the control unit 30 controls in such a manner as to giveinformation about the HOV lane as described above in the individualembodiments. After that, the processing is terminated.

As described above, according to the navigation system of the embodiment10 in accordance with the present invention, since the vehicle cannottravel in the HOV lane when only one passenger drives it, it can enablethe user to recognize as an impassable road by the same information asabout the no entry road, thereby making it unnecessary for the user tohave a particular concern about passableness of the HOV lane.Accordingly, as for the HOV lane, the user can drive with the same senseas the no entry road. Here, “handling in the same way as the no entryroad” has an influence on whether to count a stub (a confusing branchroad before a guide point) at the guidance, for example.

Incidentally, although the navigation system of the foregoing embodiment10 uses the occupant number as an example of the regulation, otherregulation according to time or model can also be used.

Embodiment 11

The navigation system of an embodiment 11 in accordance with the presentinvention is configured in such a manner as to display an HOV lane thatis decided to be impassable owing to regulation as a no entry road. Theconfiguration of the navigation system of the embodiment 11 inaccordance with the present invention is the same as that of thenavigation system of the foregoing embodiment 4. The followingdescription will be made centering on differences (in operation) fromthe navigation system of the embodiment 4.

FIG. 19 is a flowchart showing the operation of the navigation system ofthe embodiment 11. Incidentally, steps executing the same or likeprocessing to the processing in the flowcharts shown in FIG. 10 and FIG.18 are designated by the same symbols as those of FIG. 10 and FIG. 18 tosimplify the explanation.

In this processing, the map information is acquired, first (step ST31).Subsequently, the vehicle position information is acquired (step ST32).Subsequently, the route search is conducted (step ST33). Subsequently,it is checked whether the route has an HOV lane or not (step ST34). If adecision is made at this step ST34 that no HOV lane is located on theroute, since it is not necessary to display the HOV lane as the no entryroad, the processing is terminated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located, then it is checked whether only one passenger is travelingin the vehicle or not (step ST91). If a decision is made at this stepST91 that only one passenger is traveling in the vehicle, then the HOVlane is displayed on the guide map in the same manner as the no entryroad (step ST94). More specifically, the display processing unit 44creates the display data for displaying the HOV lane as the no entryroad, and delivers to the display control unit 24 within the controller20. The display control unit 24 converts the display data received tothe video signal, and delivers to the display 18 via the input/outputcontrol unit 25. Thus, as shown in FIG. 20, the HOV lane on the guidemap displayed on the display 18 is displayed in the same manner as theno entry road. After that, the processing is terminated.

On the other hand, if a decision is made at step ST91 that a pluralityof passengers are in the vehicle rather than one, then the guidanceassociated with the HOV lane is performed (step ST93). Morespecifically, the control unit 30 controls in such a manner as to giveinformation about the HOV lane as described above in the individualembodiments. After that, the processing is terminated.

As described above, according to the navigation system of the embodiment11 in accordance with the present invention, since the vehicle cannottravel in the HOV lane when only one passenger drives it, it can enablethe user to visually recognize as an impassable road by displaying it onthe guide map in the same manner as a no entry road, thereby making itunnecessary for the user to have a particular concern about passablenessof the HOV lane. Accordingly, the user can drive the HOV lane with thesame sense as the no entry road. Here, “displaying in the same way asthe no entry road” means to display it while distinguishing them bydesign such as color when displaying the no entry road and otherordinary road.

Incidentally, although the navigation system of the foregoing embodiment11 uses the occupant number as an example of the regulation, otherregulation according to time or model can also be used.

Embodiment 12

The navigation system of an embodiment 12 in accordance with the presentinvention is configured in such a manner as to display a no entry markon the HOV lane on the guide map, which is decided to be impassableaccording to the regulation. The configuration of the navigation systemof the embodiment 12 in accordance with the present invention is thesame as that of the navigation system of the foregoing embodiment 11.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 11.

FIG. 21 is a flowchart showing the operation of the navigation system ofthe embodiment 12. Incidentally, steps executing the same or likeprocessing to the processing in the flowchart shown in FIG. 19 aredesignated by the same symbols as those of FIG. 19 to simplify theexplanation.

In this processing, the map information is acquired, first (step ST31).Subsequently, the vehicle position information is acquired (step ST32).Subsequently, the route search is conducted (step ST33). Subsequently,it is checked whether the route has an HOV lane or not (step ST34). If adecision is made at this step ST34 that no HOV lane is located on theroute, the processing is terminated because it is not necessary todisplay the no entry mark on the HOV lane.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, it is checked whether only one passenger istraveling in the vehicle or not (step ST91). If a decision is made atthis step ST91 that only one passenger is traveling in the vehicle, thenthe no entry mark is displayed on the HOV lane on the map or on theguide map (step ST95). More specifically, the display processing unit 44creates the display data provided with the no entry mark to be put onthe HOV lane, and delivers to the display control unit 24 within thecontroller 20. The display control unit 24 converts the display datareceived to the video signal, and delivers to the display 18 via theinput/output control unit 25. Thus, the no entry mark is displayed onthe map displayed on the display 18 as shown in FIG. 22, for example.After that, the processing is terminated.

On the other hand, if a decision is made at step ST91 that a pluralityof passengers are in the vehicle rather than one, then the guidanceassociated with the HOV lane is performed (step ST93). Morespecifically, the control unit 30 controls in such a manner as to giveinformation about the HOV lane as described above in the individualembodiments. After that, the processing is terminated.

As described above, according to the navigation system of the embodiment12 in accordance with the present invention, since the vehicle cannottravel in the HOV lane when only one passenger is traveling in thevehicle, it can enable the user to visually recognize as an impassableroad by displaying the no entry mark as in the case of other no entryroad, thereby making it unnecessary for the user to have a particularconcern about passableness of the HOV lane. Accordingly, the user candrive the HOV lane with the same sense as the no entry road.

Incidentally, although the navigation system of the foregoing embodiment12 uses the occupant number as an example of the regulation, otherregulation according to time or model can also be used.

In addition, although the navigation system of the foregoing embodiment12 is configured in such a manner as to display the no entry mark on themap, a configuration is also possible which displays the no entry markon the guide map as shown in FIG. 23 and FIG. 24, for example. In thiscase, it can also achieve the same advantage as that of the navigationsystem of the foregoing embodiment 12.

Embodiment 13

The navigation system of the embodiment 13 in accordance with thepresent invention is configured in such a manner as to conceal the HOVlane on the guide map, which is decided to be impassable according tothe regulation. The configuration of the navigation system of theembodiment 13 in accordance with the present invention is the same asthat of the navigation system of the foregoing embodiment 11. Thefollowing description will be made centering on differences (inoperation) from the navigation system of the embodiment 11.

FIG. 25 is a flowchart showing the operation of the navigation system ofthe embodiment 13. Incidentally, steps executing the same or likeprocessing to the processing in the flowcharts shown in FIG. 19 aredesignated by the same symbols as those of FIG. 19 to simplify theexplanation.

In this processing, the map information is acquired, first (step ST31).Subsequently, the vehicle position information is acquired (step ST32).Subsequently, the route search is conducted (step ST33). Subsequently,it is checked whether the route has an HOV lane or not (step ST34). If adecision is made at this step ST34 that no HOV lane is located on theroute, since it is not necessary to conceal the HOV lane, the processingis terminated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located, then it is checked whether only one passenger is travelingin the vehicle or not (step ST91). If a decision is made at this stepST91 that only one passenger is traveling in the vehicle, then the HOVlane is not displayed on the guide map (step ST96). More specifically,the display processing unit 44 creates the display data in which the HOVlane is deleted from the guide map, and delivers to the display controlunit 24 within the controller 20. The display control unit 24 convertsthe display data received to the video signal, and delivers to thedisplay 18 via the input/output control unit 25. In this way, even ifthe HOV lane is located on the guide map displayed on the display 18 asshown in FIG. 26 (a), for example, the HOV lane is deleted as shown inFIG. 26 (b). After that, the processing is terminated.

On the other hand, if a decision is made at step ST91 that a pluralityof passengers are in the vehicle rather than one, then the guidanceassociated with the HOV lane is performed (step ST93). Morespecifically, the control unit 30 controls in such a manner as to giveinformation about the HOV lane as described above in the individualembodiments. After that, the processing is terminated.

As described above, according to the navigation system of the embodiment13 in accordance with the present invention, since the vehicle cannottravel in the HOV lane when only one passenger is traveling in thevehicle, it does not display the HOV lane on the guide map because it isimpassable. Thus, the user can drive in accordance with the informationabout the road displayed without being aware of the HOV lane.

Incidentally, although the navigation system of the foregoing embodiment13 uses the occupant number as an example of the regulation, otherregulation according to time or model can also be used.

Embodiment 14

The navigation system of an embodiment 14 in accordance with the presentinvention is configured in such a manner as to give information about alane change at a suitable timing considering the presence/absence of thefollowing vehicle at an entrance/exit section of the HOV lane. Theconfiguration of the navigation system of the embodiment 14 inaccordance with the present invention is the same as that of thenavigation system of the foregoing embodiment 8. The followingdescription will be made centering on differences (in operation) fromthe navigation system of the embodiment 8.

FIG. 27 is a flowchart showing the operation of the navigation system ofthe embodiment 14 centering on the lane change processing. Incidentally,steps executing the same or like processing to the processing in theflowchart shown in FIG. 15 are designated by the same symbols as thoseof FIG. 15 to simplify the explanation.

In the lane change processing, the map information is acquired, first(step ST31). Subsequently, the vehicle position information is acquired(step ST32). Subsequently, the route search is conducted (step ST33).Subsequently, it is checked whether the route has an HOV lane or not(step ST34). If a decision is made at this step ST34 that no HOV lane islocated on the route, the lane change processing is terminated becausethe lane change between the HOV lane and another lane is not necessary.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether an entrance/exitbetween the HOV lane and another lane is placed on the HOV lane (stepST71). More specifically, the HOV lane entrance/exit extracting unit 39extracts, when the decision result acquired from the HOV lane decisionunit 38 indicates that the route includes the HOV lane, an entrance/exitsection between the lanes other than the HOV lane and the HOV lane, anddelivers to the control unit 30. If a decision is made at this step ST71that the entrance/exit between the HOV lane and another lane is notplaced on the HOV lane, the entrance/exit information processing isterminated.

On the other hand, if a decision is made at step ST71 that theentrance/exit is placed between the HOV lane and another lane on the HOVlane, an HOV lane entrance/exit section position is acquired (stepST72). More specifically, the control unit 30 acquires, when theentrance/exit position data is delivered from the HOV lane entrance/exitextracting unit 39, the section indicated by the entrance/exit positiondata as the HOV lane entrance/exit section position.

Subsequently, detection of the following vehicle is performed (stepST101). More specifically, the following vehicle detecting unit 33detects the presence/absence of the following vehicle on the basis ofthe following vehicle signal delivered from the following vehicledetecting sensor 16, and delivers the detection result to the controlunit 30.

Subsequently, a safe timing considering the following vehicle iscalculated, and the information is given about the lane change at theHOV lane entrance/exit (step ST102). More specifically, when a detectionresult that no following vehicle is present is delivered from thefollowing vehicle detecting unit 33, the control unit 30 forms a messagesaying that it is a good timing for the lane change, and delivers it toat least one of the display processing unit 44 and voice messagecreating unit 45.

When the message is delivered from the control unit 30, the displayprocessing unit 44 creates the display data for displaying the message,and delivers it to the display control unit 24 within the controller 20.The display control unit 24 converts the display data delivered from thedisplay processing unit 44 to the video signal, and delivers to thedisplay 18 via the input/output control unit 25. Thus, the messagestating that it is the good timing for the lane change is displayed onthe screen of the display 18.

In addition, the voice message creating unit 45 forms a voice messagefrom the message saying that it is the good timing for the lane changedelivered from the control unit 30, and delivers to the voiceinformation unit 46 as the voice data. The voice information unit 46converts the voice data delivered from the voice message creating unit45 to the voice signal, and delivers to the voice output device 19.Thus, the voice output device 19 outputs the voice informationindicating that it is the good timing for the lane change.

The display processing unit 44, display control unit 24, display 18,voice message creating unit 45, voice information unit 46 and voiceoutput device 19 of the present embodiment 14 correspond to a guidanceunit in accordance with the present invention.

As described above, according to the navigation system of the embodiment14 in accordance with the present invention, since it gives informationabout the good timing for the lane change in accordance with thepresence/absence of the following vehicle, the user can perform safedriving comfortably.

Embodiment 15

The navigation system of an embodiment 15 in accordance with the presentinvention is configured in such a manner as to give information bydeciding the passable/impassable state of an HOV lane in accordance withthe vehicle information. The configuration of the navigation system ofthe embodiment 15 in accordance with the present invention is the sameas that of the navigation system of the foregoing embodiment 8. Thefollowing description will be made centering on differences (inoperation) from the navigation system of the embodiment 8.

FIG. 28 is a flowchart showing the operation of the navigation system ofthe embodiment 15 centering on the information processing.

In the information processing, vehicle information is extracted, first(step ST111). More specifically, the vehicle information extracting unit35 extracts the vehicle information on the vehicle such as thatindicating the dimensions of the vehicle (large-sized/medium-sized) fromthe vehicle in which the navigation system is mounted, and delivers tothe control unit 30.

Subsequently, the type of the vehicle is checked whether it can passthrough the HOV lane (step ST112). More specifically, when the HOV lanedecision unit 38 decides that the road indicated by the map informationacquired from the map information acquiring unit 31 includes the HOVlane, the control unit 30 checks whether the vehicle with the typeindicated by the vehicle information acquired at step ST111 is passablethrough the HOV lane or not.

If a decision is made at this step ST112 that it is a vehicle passablethrough the HOV lane, then the information is given about the HOV lane(step ST113). More specifically, the control unit 30 carries out controlin such a manner as to give information about the HOV lane as describedin the individual embodiments described above. More specifically, thecontrol unit 30 forms a message for guidance of the HOV lane, anddelivers it to at least one of the display processing unit 44 and voicemessage creating unit 45.

When the message is delivered from the control unit 30, the displayprocessing unit 44 creates the display data for displaying the message,and delivers to the display control unit 24 within the controller 20.The display control unit 24 converts the display data delivered from thedisplay processing unit 44 to the video signal, and delivers it to thedisplay 18 via the input/output control unit 25. Thus, the message forguidance of the HOV lane is displayed on the screen of the display 18,for example.

In addition, the voice message creating unit 45 forms a voice messagefrom the message guidance of the HOV lane delivered from the controlunit 30, and delivers it to the voice information unit 46 as the voicedata. The voice information unit 46 converts the voice data deliveredfrom the voice message creating unit 45 to the voice signal, anddelivers it to the voice output device 19. Thus, the voice output device19 outputs the voice information about the HOV lane. After that, theprocessing is terminated.

On the other hand, if a decision is made at step ST112 that the vehicleis impassable through the HOV lane, then ordinary information is givenwithout considering the HOV lane (step ST114). More specifically, thecontrol unit 30 controls in such a manner as to perform ordinaryguidance without guidance of the HOV lane. More specifically, thecontrol unit 30 forms a message for giving ordinary guidance withoutconsidering the HOV lane, and delivers it to at least one of the displayprocessing unit 44 and voice message creating unit 45.

When the message is delivered from the control unit 30, the displayprocessing unit 44 creates the display data for displaying the message,and delivers to the display control unit 24 within the controller 20.The display control unit 24 converts the display data delivered from thedisplay processing unit 44 to the video signal, and delivers it to thedisplay 18 via the input/output control unit 25. To be concrete, themessage for guidance of not using the HOV lane is displayed on thescreen of the display 18.

In addition, the voice message creating unit 45 forms a voice messagefrom the message giving ordinary information without considering the HOVlane delivered from the control unit 30, and delivers it to the voiceinformation unit 46 as the voice data. The voice information unit 46converts the voice data delivered from the voice message creating unit45 to the voice signal, and delivers it to the voice output device 19.Thus, the voice output device 19 outputs the voice information that theHOV lane is unavailable, that is, the ordinary information withoutconsidering the HOV lane. After that, the processing is terminated.

The display processing unit 44, display control unit 24, display 18,voice message creating unit 45, voice information unit 46 and voiceoutput device 19 of the present embodiment 15 correspond to the aguidance unit in accordance with the present invention.

As described above, according to the navigation system of the embodiment15 in accordance with the present invention, since there is a road as towhich the passableness of the HOV lane is decided depending on thevehicle, guidance considering the vehicle enables the user to drivecomfortably in accordance with the guidance.

Embodiment 16

The navigation system of an embodiment 16 in accordance with the presentinvention is configured in such a manner as not to give informationabout a branch road diverging only from an ordinary lane in a routesection passing through an HOV lane. The configuration of the navigationsystem of the embodiment 16 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 8.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 8.

FIG. 29 is a flowchart showing the operation of the navigation system ofthe embodiment 16 centering on branch road information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 15 are designated by the samesymbols as those of FIG. 15 to simplify the explanation. Here, thebranch road information processing makes a decision as to: (a) whetherto give information about a branch road or not; (b) whether to adopt itas a target of a guidance display or not; and (c) whether to adopt it asa target of the voice information or not.

In the branch road information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane or not (step ST34). If a decision is made at this step ST34that no HOV lane is located, since it is not necessary to consider anordinary lane running side by side with an HOV lane, the branch roadinformation processing is terminated.

On the other hand, if a decision is made at step ST34 that the HOV laneis located on the route, then it is checked whether there is a branchroad diverging only from an ordinary lane in the route section passingthrough the HOV lane or not (step ST121). More specifically, the controlunit 30 checks whether there is a branch road diverging only from theordinary lane in the route section passing through the HOV lane on thebasis of the map information acquired from the map information acquiringunit 31. If a decision is made at this step ST121 that there is not abranch road diverging only from the ordinary lane in the route sectionpassing through the HOV lane, then the branch road informationprocessing is terminated.

On the other hand, if a decision is made at step ST121 that there is abranch road diverging only from the ordinary lane in the route sectionpassing through the HOV lane, even if a bifurcation flag (whichindicates that guidance is necessary without exception) is set at a forkwhere the branch road diverges only from the ordinary lane, theinformation is not given (step ST122). More specifically, the controlunit 30 does not execute the processing for guidance. After that, thebranch road information processing is terminated.

As described above, according to the navigation system of the embodiment16 in accordance with the present invention, as for the branch roadconnected to the ordinary lane, since it is impossible to enter thebranch road during driving in the HOV lane, it can suppress unnecessaryguidance for a user.

Embodiment 17

The navigation system of an embodiment 17 in accordance with the presentinvention is configured in such a manner as not to give informationabout a branch road diverging only from an HOV lane in a route sectionpassing through an ordinary lane. The configuration of the navigationsystem of the embodiment 17 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 8.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 8.

FIG. 30 is a flowchart showing the operation of the navigation system ofthe embodiment 17 centering on branch road information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 15 are designated by the samesymbols as those of FIG. 15 to simplify the explanation. Here, thebranch road information processing makes a decision as to: (a) whetherto give information about a branch road or not; (b) whether to adopt itas a target of a guidance display or not; and (c) whether to adopt it asa target of the voice information or not.

In the branch road information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, the route search isconducted (step ST33). Subsequently, it is checked whether the route hasan HOV lane running alongside the route or not (step ST131). Morespecifically, the control unit 30 acquires the route data from the routestorage unit 37 and decides whether there is an HOV lane runningalongside the route indicated by the route data. If a decision is madeat this step ST131 that no HOV lane is located which runs alongside theroute, since it is not necessary to consider an HOV lane running side byside with an ordinary lane, the branch road information processing isterminated.

On the other hand, if a decision is made at step ST131 that the HOV lanewhich runs alongside the route is located, then it is checked whetherthere is a branch road diverging only from the HOV lane in the routesection passing through the ordinary lane or not (step ST132). Morespecifically, the control unit 30 checks whether there is a branch roaddiverging only from the HOV lane in the route section passing throughthe ordinary lane on the basis of the map information acquired from themap information acquiring unit 31. If a decision is made at this stepST132 that there is not a branch road diverging only from the HOV lanein the route section passing through the ordinary lane, then the branchroad information processing is terminated.

On the other hand, if a decision is made at step ST132 that there is abranch road diverging only from the HOV lane in the route sectionpassing through the ordinary lane, even if a bifurcation flag is set ata fork where the branch road diverges only from the HOV lane, theinformation is not given (step ST133). More specifically, the controlunit 30 does not execute the processing for guidance. After that, thebranch road information processing is terminated.

As described above, according to the navigation system of the embodiment17 in accordance with the present invention, as for the branch roadconnected only to the HOV lane, since it is impossible to enter thebranch road during driving in the ordinary lane, it can suppressunnecessary guidance for a user.

Embodiment 18

The navigation system of an embodiment 18 in accordance with the presentinvention is configured in such a manner as not to give informationabout a branch road diverging only from an HOV lane in a route sectionpassing through an ordinary lane. The configuration of the navigationsystem of the embodiment 18 in accordance with the present invention isthe same as that of the navigation system of the foregoing embodiment 8.The following description will be made centering on differences (inoperation) from the navigation system of the embodiment 8.

FIG. 31 is a flowchart showing the operation of the navigation system ofthe embodiment 18 centering on branch road information processing.Incidentally, steps executing the same or like processing to theprocessing in the flowchart shown in FIG. 15 are designated by the samesymbols as those of FIG. 15 to simplify the explanation. Here, thebranch road information processing makes a decision as to: (a) whetherto give information about a branch road or not; (b) whether to adopt itas a target of a guidance display or not; and (c) whether to adopt it asa target of the voice information or not.

In the branch road information processing, the map information isacquired, first (step ST31). Subsequently, the vehicle positioninformation is acquired (step ST32). Subsequently, it is checked whetheran HOV lane is located ahead of the vehicle or on the vehicle'straveling road (step ST141). More specifically, the control unit 30checks whether an HOV lane is located on the road ahead of the vehicleindicated by the map information acquired from the map informationacquiring unit 31 or in the road in which the vehicle is traveling onthe basis of the current position acquired from the current positiondetecting unit 32. If a decision is made at this step ST141 that no HOVlane is located ahead of the vehicle or on the vehicle's traveling road,since it is not necessary to consider the HOV lane, the branch roadinformation processing is terminated.

On the other hand, if a decision is made at step ST141 that the HOV laneis located ahead of the vehicle or on the vehicle's traveling road, thenit is checked whether the vehicle is traveling in the HOV lane or not(step ST142). More specifically, the control unit 30 checks whether thecurrent position acquired from the current position detecting unit 32 ison the HOV lane which is decided as being located at step ST141.

If a decision is made at this step ST142 that the vehicle is travelingin the HOV lane, then the information is not given even if thebifurcation flag is set at a fork diverging only from the ordinary lane(step ST143). More specifically, the control unit 30 does not executethe processing for guidance. After that, the branch road informationprocessing is terminated.

On the other hand, if a decision is made at this step ST142 that thevehicle is not traveling in the HOV lane, then the information is notgiven even if the bifurcation flag is set at a fork diverging only fromthe HOV lane (step ST144). More specifically, the control unit 30 doesnot execute the processing for guidance. After that, the branch roadinformation processing is terminated.

As described above, according to the navigation system of the embodiment18 in accordance with the present invention, as for the branch roadconnected to the ordinary lane, since it is impossible to enter thebranch road during driving in the HOV lane, it can suppress unnecessaryguidance for a user. Likewise, as for the branch road connected to theHOV lane, since it is impossible to enter the branch road during drivingin the ordinary lane, it can suppress unnecessary guidance for a user.

INDUSTRIAL APPLICABILITY

A navigation system in accordance with the present invention can enablea user to visually recognize in which road the user is driving when adecision is made that a road indicated by map information includes anHOV lane. Accordingly, it is suitable for an application to a navigationsystem for guiding the user to a destination via a route including anHOV lane.

1. A navigation system comprising: a map information acquiring unit foracquiring map information in which a road is defined by a single linkregardless of whether an HOV lane is juxtaposed on the road or not anddata on the link contains information as to whether an HOV lane isjuxtaposed or not; an HOV lane decision unit for deciding whether an HOVlane is included in a road represented by the map information acquiredby the map information acquiring unit or not; a road number processingunit for performing, when the HOV lane decision unit decides that theHOV lane is included, processing of adding information representing theHOV lane to a road number of the road including the HOV lane; and adisplay control unit for causing the road number passing through theprocessing by the road number processing unit to be displayed; or avoice information unit for causing the road number passing through theprocessing by the road number processing unit to be output in voice. 2.A navigation system comprising: a map information acquiring unit foracquiring map information; an HOV lane decision unit for decidingwhether an HOV lane is included in a road represented by the mapinformation acquired by the map information acquiring unit or not; acontrol unit for acquiring, when the HOV lane decision unit decides thatthe HOV lane is included, a road number of the road including the HOVlane, and for acquiring, when only a road name of the road is obtainedwithout being able to acquire the road number, the road number from theroad name; and a display control unit for causing the road numberacquired by the control unit to be displayed; or a voice informationunit for causing the road number acquired by the control unit to beoutput in voice.
 3. The navigation system according to claim 2, furthercomprising: a road number processing unit for performing processing ofadding information representing an HOV lane to the road number acquiredby the control unit, wherein the display control unit causes the roadnumber passing through the processing by the road number processing unitto be displayed.
 4. The navigation system according to claim 2, furthercomprising: a road number processing unit for performing processing ofadding information representing an HOV lane to the road number acquiredby the control unit, wherein the voice information unit causes the roadnumber passing through the processing by the road number processing unitto output in voice.